Units Sold 4. A new tech start-up is trying to sell their app through the various app stores. Looking at similar apps already on the market, they have created a sales demand graph (shown below). The intercepts mean that at $0 they would expect to sell 10,000 copies of their app, but would sell none if they charged $5. a. The units sold follows the equation U = 10000 i . - - 2000P. The money from sales is equal to the units ' sold times the price P of the unit. Write an equation for sales as a function of price. Demand Curve b. The upfront costs of creating the app, plus continued maintenance and service, is represented by the equation C = 2000 + 0.1U. Write an equation Price (5) for costs as a function of price. c. The profit from selling the app is equal to sales minus costs. Write an equation for profit in relation to price